Electrodeposition of nickel



' 3,255,096 ELECTRODEPOSITION OF NICKEL Jack L. Towle, East Cleveland, Dale G. Block, Cleveland, and Raymond E. Bailey, Mentor, Ohio, assignors to The Harshaw (Chemical Company, Cleveland, Ohio, a corporation of Ohio No Drawing. Filed Nov. 1, 1963, Ser. No. 320,939

9 Claims. (Cl. 204-49) This invention relates to the electrodeposition of fully bright nickel plate. More particularly, this invention relates to the use of a specific class of saturated heterocyclic compounds containing acetylenic substituents as one component of a brightener system for the electrodeposition of fully bright nickel.

According to the present invention, fully bright nickel may be deposited from any solution of nickel ions designed for plating nickel. All standard aqueous solutions designed for electroplating nickel may be used. These solutions contain at least one of the following salts: nickel sulfate, nickel chloride, nickel fluoborate and nickel sulfamate, wherein the solution is adjusted to an operating concentration of nickel. Included among the various baths useful with the present invention are (1) the various barrel plating baths generally comprising nickel sulfate and nickel chloride as the source of the nickel ion and buffer systems comprising boric acid alone or in conjunction with magnesium sulfate or ammonium chloride, (2) the all-chloride bath designed for use where a high current density is desired, comprising nickel chloride as the source of nickel ion and boric acid as the butler, (3) the cold bath designed for use in coating objects not subject to corrosive conditions such as jewelry, comprising nickel sulfate as a source of nickel ion and boric acid and ammonium chloride comprising the buffer system, (4) the fluoborate bath comprising nickel fluoborate as the source of nickel ion and free boric acid as the buffer alone or in combination with fluoboric acid, (5) the common Wattstype bath designed for all purpose nickel plating and generally corn-prising nickel sulfate and nickel chloride as the source of nickel ion buifered with boric acid, and (6) the sulfamate bat-h.

United States Patent 0 Other ingredients are usually added to these basic constituents in order to tailor each solution for accomplishing a specific efiect and result. Included among these ingredients are wetting agents such as the anionic surfactants, or-' ganic brighteners other than those of the present invention and the like.

It has been known prior to the present invention to employ various water-soluble acetylenic compounds as brightener-s in nickel plating baths. Some water soluble acetylenic compounds function well as brighteners without cooperative addition agents While other water soluble acetylenic compounds function only as brighteners in conjunction with one or more cooperative addition agents.

It is generally understood by those skilled in the art that these water soluble acetylenic compounds, particularly those of relatively low molecular weight, manifest varying degrees of adsorption on the surface of the cathode being electroplated. It is also generally understood that this adsorption on the surface is desirable when the cathode is to be electroplated with a nickel deposit having full brightness.

The present invention is concerned with brightener systems comprising (a) at least one organic sulfo-oxygen Patented June 7, 1966 H2 (at (a 0 112-0 EC R1 wherein n is an integer of from O-to 1 inclusive, A represents a radical selected from the group consisting of and S-, X represents an anion and R and R represent monovalent organic radicals. Thus the monovalent substituent represented by R can he monovalent organic radicals, examples of which are the monovalent alkyl, al-

kenyl, aralkyl, alkynyl, cyanoalkyl radicals and aromatic radicals and heterocyclic radicals forming part of aliphatic hydrocarbon radicals. R is only present in the quaternary salt, R may be a monovalent organic radical free of triple bonds such as a lower saturated hydrocarbon radical, a heterocyclic radical or hydrogen. When n is 1, Formula I represents aclassof quaternary ammonium salts.

The present invention is based on the discovery that the compounds as defined in Formula I may advantageously be combined with the hereinbefore mentioned sulfooxygen compounds to provide an excellent brightener system in baths designed for electrodepositing fully bright nickel.

These compounds may be employed either as unquaternized compounds or they may be employed as the quaternary ammonium saltsthereof having a second acetylenic substituent or some other organic radical pendant from the in-ring nitrogen atom or they may be employed as a mixture of two or more of the compounds.

It is'quite surprising and unexpected that the compounds of the present invention may be used so elfectively and universally as a class with the organic sulfo-oxygen compounds to providea complete series of operative brightener systems in view of the fact it has been impossible to predict the characteristics of nickel deposits from baths containing acetylenic compounds as brighteners; the action of acetylenic compounds on the cathode surface is not adequately understood. Moreover, it is especially surprising that the compounds of Formula I may be used universally as a class since the piperidino analogues of these compounds are lacking utility as brighteners because of poor brightening characteristics.

The corn-pounds of the instant class are also advan tageously produced in high yields and may be obtained substantially free of impurities, thus providing a lowcost source of commercially acceptable brighteners. The fact that-the compounds of the present invention provide a class of compounds all of which may be used as brighteners is also surprising and unexpected inasmuch as certain classes of compounds having analogous heterocyclic type unsaturated rings containing nitrogen in the nucleus including varying numbers of compounds that do not act very well as brighteners. Moreover, many of these compounds, while being extremely good brighteners, are obtained only in poor yields and must be separated from a tarry mass making such compounds exorbitantly expensive. Such compounds include the quaternary ammonium heterocyclic compounds containing the quinoline, acridine and/or pyridine nuclei.

Also, it is surprising that these saturated ring compounds allow a greater range of current densities for brightness than do the analogous unsaturated ring compounds. Through the use of the saturated brightenrs of the present invention it is possible to obtain a nickel deposit having a greater area of brightness for any given article of complex shape than can be obtained on nickel deposited using the unsaturated analogues.

The present invention is carried into effect merely by adding one or more of the compounds defined by Formula I with one or more of the hereinbefore mentioned organic sulfo-oxygen compounds to an aqueous solution of one or more of the required nickel salts.

The resulting solution may be employed advantageously as an electroplating bath for the deposition of fully bright nickel. When employed with Watts-type, sulfamate or fiuoborate baths, the brightener systems of the present invention provide a solution which can be operated effectively at current densities ranging from to 200 amps. per square ft. and preferably at current densities ranging from 25 to 100 amps. per square ft. The baths prepared according to the present invention may be operated at temperatures in the range of from 100 F. to 170 F. and preferably from.130 F. to 165 F.

In adjusting the composition of the nickel plating baths of the present invention, it is preferred that the resulting solution have a pH between 3.5 and 4.5. This pH range is however not critical; very satisfactory results are obtained from solutions having a pH value anywhere in the range of from 2 to 5.5. As in most cases, theetfective concentrations for each member of the class of compounds of Formula I vary slightly and are partially dependent on the over-all bath composition and the plating conditions (temperature, current densities, etc.). The compounds defined by Formula I are effective in amounts as low as .005 g./l. and may be used advantageously in amounts up to 0.6 g./l. Preferably the bath should contain at least 0.01 g./l. of a compound defined by Formula 1. Concentrations in excess of 0.6 g./l. while not being harmful provide no added advantage.

The complementing compounds (the organic sulfooxygen compounds) of the brightener systems of the present invention may be advantageously employed in similar amounts as the brighteners themselves. Generally it has been found, however, that the sulfo-oxygen compounds should be present in amounts ranging from about 2.0 g./l. to about 5.0 g./l. In some instances amounts as high as 40 to 50 g./l. may advantageously be used.

Using the brightener systems of the present invention, fully bright nickel may advantageously be deposited at almost any thickness. The only criteria to be used in controlling the thickness are the cost of excessive nickel and the degree of ductility demanded. Maximum ductility is obtained at the minimum thicknesses required for obtaining a fully bright plate. Using baths prepared according to the present invention, a build-up of about 0.0001 to 0.0005 inch of nickel produces a highly ductile, fully bright plate. Where a heavy plate is of primary concern, fully bright plates may be deposited to a thickness up to 0.1 inch or even higher. It is preferred, however, that the thickness of the nickel deposit be kept between 0.001 inch and 0.01 inch. A nickel deposit having a thickness in this range is fully bright and ductile and provides the protection usually required for use in most environments.

Nickel electroplating baths particularly useful in combination With the brightener systems of the present invention include the Watts-type and fiuoborate type baths having increased nickel content. Such baths are designed for use with organic brighteners in general; they may be operated at the higher current densities desirable for the effective use of the instant organic brighteners. For purposes of the present invention, the preferred Wattstype bath essentially comprises an overall nickel content ranging from 70 to 115 g./l. provided by 270 g./l. to about 450 g./l. of nickel sulfate and from about 20 g./l. to about g./l. of nickel chloride with about 30 to 40 g./l. of boric acid as the buffer and the preferred fluoborate type bath essentially comprises an over-all nickel content ranging from 75 to g./l. provided by about 440 g./l. of nickel fluoborate with about 30 g./l. of boric acid as the buffer.

For purposes of the present invention, .boric acid is preferred as the buffer-as an additive to maintain the desired pH. However, oxalic acid, borax (sodium tetraborate), formic acid and other compounds commonly known to have utility as buffers, may be used with the baths of the present invention with no apparent undesirable effects.

Illustrative examples of wetting agents which may be employed in the baths of the present invention include a great majority of the anionic surfactants. The sulfate type may particularly be used. Included among this type are the alkylsulfates, aral kylsulfates, alkylsulfonates, and the aralkylsulfonates.

The use of a wetting agent in baths prepared according to the present invention is optional; excellent deposits are obtained from baths having no wetting agent.

Illustrative examples of the organic sulfa-oxygen compounds to be employed as a co-brightener or cooperating addition agent of the present invention include the unsaturated aliphatic sulfonic acids, and alkali metal, ammonium, magnesium, and nickel salts thereof such as sodium vinyl sulfonate, sodium allyl sulfonate, diallylsulfone, Na-fl-styrene sulfonate, and the like;

The mono and binuclear sulfonic acids, and alkali metal, ammonium, magnesium, and nickel salts thereof such as benzene sulfonic acid, sodium benzene sulfonate, nickel benzene sulfonate, sodium p-toluene sulfonate, p-chlorobenzene sulfonic acid, sodium p-bromobenzene sulfonate, 1,2-dichlorobenzene sulfonic acid, sodium m-benzene disulfonate, nickel m-benzene disulfonate, l-amino-2,5-benzene sulfonic acid, .0, m, and p-sulfobenzaldehyde, sulfonated naphthalene sulfone, and the like;

The aromatic sulfinic acids, and alkali metal, ammonium, magnesium, and nickel salts thereof such as sodium benzene sulfinate, sodium p-toluene sulfinate, dichlorobenzene sulfinic acid, and the like;

The mononuclear and polynuclear aromatic sulfonamides and sulfonimides such as benzenesulfonamide, p toluenesulfonamide, saccharin, benzylsulfonamide, N,N- dimethyl-p-toluenesulfonamide, N,N-dicarboxyethyl benzenesulfonamide, dibenzenesulfonamide, p,p'-oxy-bis(dibenzene sulfonimide, N,N-bis-(phenyl sulfonyl)-4,4' biphenyl disulfonamide and the like;

The binuclear aromatic sulfonic acids, and alkali metal, ammonium, magnesium, and nickel salts thereof such as 2- naphthalene sulfonic acid, 1,5- or 2,7-naphthalene disulfonic acid, nickel l,5- or 2,7-naphthalene disulfonate, naphthalene trisulfonic acid, diphenyl p,p'-disulfonic acid, 2-naphthol-3,fi-disulfonic acid, 1-naphtl1ylamine-3,6,8- trisulfonic acid, and the like;

The heterocyclic sulfonic acids, and alkali metal, ammonium, magnesium, and nickel salts thereof including thiophene sulfonic acid, 2-(4-pyridyl) ethyl sulfonic acid, 2-(2-pyridyl) ethyl sulfonic acid, and the like. Additionalsulfo-oxygen compounds useful with present invention include those disclosed in US. Patents 2,757,133 and 2,766,284 which are incorporated herein by reference.

The examples of the compounds embraced by Formula I include the monoand (ii-substituted thiazines, thiazine dioxides, piperidones, piperazines and the quaternary ammonium salts thereof including the halides, arylsulfonates, sulfates, perchlorates and the like, wherein R of Formula I may be hydrogen or a monovalent saturated hydrocarbon radical derived from-hydrocarbons containing from 1-16 .carbon atoms including methane, ethane, etc. through hexadecane; monovalent unsaturated hydrocarbon radicals derived from the monoand polyolefins, the monoand polyacetylenic compounds and those polyunsaturated compounds containing both double bonds and triple, bonds derived from compounds having '31 carbon atoms including propene, 'butene, etc. through decene; butadiene, pentadiene, etc. through decadiene; propyne, butyne, etc. through decyne; the ethenyl, propenyl, butenyl radicals containing at least one triple bond and having from 4-10 carbon atoms; monovalent aromatic substituted aliphatic radicals derived from lower alkyl benzenes including toluene (phenyl methane), phenylethane and the like, and lower alkyl substituted benzenes including their 'homologues such as xylene and the like and alkyl benzenes substituted with fluorine, chlorine, bromine or the like; monovalent nitriles derived from cyanoalkyls such as B-cyanoethyl and the like; monovalent hydroxyalkyls derived from compounds having from lcarbon atoms such as methanol (hydroxymethane), ethanol through pentanol (hydroxypentane) and the like; monovalent cycloalkyls derived from compounds having from 36 carbon atoms such as cyclopropane through cyclohexane and the like; and whereoin R of Formula I represents hydrogen a lower alkyl having from 1-5 carbon atoms an a radical represented by the formula wherein A, *R and X have the same meaning as above and includes radicals derived from thiazine, thiazine dioxide, piperidone, and piperizine.

Preferably, however, R represents lower alkyl radicals having from1-6 carbon atoms, monounsaturated alkenyl and alkynl radicals having from 3-6 carbon atoms, benzyl and B-cyanoethyl and preferably R represents hydrogen.

As hereinbefore indicated when n is 1, the compounds of Formula I represent quaternary ammonium salts and X is any anion of a water soluble acid. The particular anion is not important and has little if any effect on brightening properties of these compounds. The only property the anion must have is that it be capable of forming the quaternary salt with the tertiary nitrogen of the present compounds. Examples of useful anions represented by X include, of course, the strongly anionic single valent halogen radicals, fluoride, chloride, bromide and iodide; the single valent aryl sulfonates, benzenesulfonate and the like and the single valent peroxyhalogenates; perchlorate and the like.

Specific names of some of the compounds of Formula I include N,N-dipropargylthiazinium-1,l-dioxide bromide, N,N dipropargylthiazinium 1,1 dioxide benzenesulfonate, N allyl N propargylthiazinium 1,1 dioxide bromide, N benzyl N propargylthiazinium 1,1 dioxide bromide, N propargylthiazine 1,1 dioxide, 1,4 bis- (N propargylthiazinium 1,1 dioxide bromide) butyne 2,1,4 bis(N thiazine 1,1 dioxide) butyne 2;

4-keto-1-methyl-l-propargyl piperidinium bromide, N-

For instance a procedure for preparing the N-substi tuted thiazine 1,1-dioxide compounds of the present invention see A. C. Bellaart, Rec. Trav. Chim., 81., 156 (1962).

The saturated ring compounds (thiazine, thiazine-1,1- dioxide, etc.) themselves are well known. Effective methods for their preparation are described in the following:

The preparation of 1,4-thiazine is disclosed in an article by Cymermon-Craig et al., Chemistry and Industry, 1954, 1455; and the preparation'of 1,4-piperidone is disclosed in an article by Ruzicks et al., Helv. Chim. Acta 1920, 3, 806, and the preparation of symmetrical double molecules containing two saturated rings is disclosed in an article by Ford et al., J. Am. Chem. Soc.- p. 2433 (1949).

In order that those skilled in the art may better understand how the present invention can be carried into effect, the following examples are given way of illustration and not by way of limitation. All parts and percentages are by weight unless otherwise specified.

The following table includes a series of bath compositions formulated according to the present invention. Each of the compositions set forth therein is used to deposit fully bright nickel plate over a broad range of current densities and at temperatures anywhere within the hereinbefore indicated range.

TAB LE Nickel Salts, g./l.

Brightener Present Boric Acid Wetting Agents, g'./l.

Buffer, g./1.

Organic Su1fohoxy gen'cpd g.

Invention, g. ll.

Nickel chloride, nickel sulfate 250.

Nickel chloride, 150; nickel sulfate, 250.

Nickel chloride, 40; nickel sulfate, 250.

Nickel tiuoborate, 300

Nickel chloride, nickel sulfamate 450. Nickel chloride,

300; nickel sulfate 30.

Nickel chloride, 40; nickel sulfate, 250.

See footnotes at end of table.

p,p0xy-bis (dibenzenesulfonimide), 3.0.

Saccharin (Na Salt), 1.0; Bi(dibenzenesulfonamide), 3.0. Saccharin (Na Salt), 2.0;

Allyl sulfonate (N a Salt),

Saccharin (Na Salt), 2; Benzene sulfonic acid, 5.

Benzene sulfonic acid, 5;

Bcnzencsultonamrde, 1.

N ,N-dipropargylthiazinium-Ll-dioxidc bromide, O

.07. N,N-dipropargylthiaziniurn-l,l-dioxide benzene sulfonate, 0.1. N -propargylthiazine-1,1-

dioxide, 0.07.

N-allyl-N-propargylthiazinium-1,1-dixoide bromide, 0

.12. N,N-dipropargylthiazinium bromide, 0.06.

4-keto-1-methyl-1-propargylpip2eridinium bromide, 0.1 5

N,N-dipropargylthiazinium-1,1-dioxide bromide,

0.28. N-propargylpiperidone, 0.1..

N-propargylthiazine-1,1-

dioxide, 0.1; N-benzyl-N- propargylthiazinium-1,1- dioxide bromide, 0.12.

N-lhenyl, N-propargylpiperazinc.

Sodium 7-ethyl-2 methyl undecyl sulfate, 0.04.

Dihexyl-ester of sodium sulfe succinic acid, 0.1.

TAB LE-Continued Ex. No. Nickel Salts, g./l. Organic Sulio-oxygen cpd., Brightener Present Wetting Agents, g./1. Boric Acid pH g./l. Invention, g./l. Butler, g./l.

XI Nickel chloride, 40; nickel Saccharin (Na Salt), 2; N-propargylthiazine-1,1- Dihexyl-ester of sodium 40 3. 7

sulfate, 250. Thiophene sulionic acid, dioxide, 0.07. sulfo succinic acid, 0.1.

.5. XII d0 Saccharin (Na Salt), 1; N ,N-dipropargylthiazin- Sodium lauryl sulfate, 0.05 40 4. 2

Allyl sulfonate (Na Salt), ium-1,1-dioxide perchl0- 0&5; l2)ibenzenesulionamrate, 0.01. 1 e, XIIL--- do Bi(dibenzenesulfonarnide), N,N-dipropargylthiazin- 40 4.

3; Benzene sulfonic acid, ium dioxide bromide, 2; Benzenesulfonamide, 1; Sulfonated Naphthalene sulfone, 1. XIV do Naphthalene disulfonate, 1; l-(N-propargylthiazinium- Dihexyl ester of sodium 40 4.0

p,pOxy-bis(dibenzene- 1,1-dioxide bromide) -4- sulfo succinic acid, 0.02; sulfonimide), 3. (keto l-propargyl-piperi- Sodium 2-ethyl l-hexyl dinium bromide) butynesulfate, 0.02. 2, 5.0. XV do Bi(dibenzenesulfonamide), 1,4-bis(N-propargylthiazin- Sodium lauryl sulfate, 0.1... 40 5. 0

2; Naphthalene disulfoium-l,1-dioxide)butyne-2, hate, 1. 0.1. XVI Nickel fiuoborate, 425 Benzene sulfonic acid, 5; N-propargylthiazine-1,1- Sodium 2-ethyl 1 hexyl 35 2. 2

Dibenzenesulfonamide, 2. dioxide, 0.07. sulfate, 0.04.

1 Bath also contained 0.01 g./l. of allyl quinaldinium bromide a well known brightener for nickel. 2 Bath also contained 0.05 g./1. of ethylene cyanohydrin a well known brightener for nickel.

As a further refinement of the present invention, it has been found that the compounds embraced by Formula I, where A represents the radicals 0 0 and =SO -may be used to provide a bath for depositing a fully bright nickel coating having excellent chromium receptivity over a wide range of current densities. Nickel plates deposited from baths containing this preferred group-of compounds can be chromium plated, stripped of the chromium plate, and replated with chromium. The stripping and replating may be performed several times with no apparent decrease in chromium receptivity.

The excellent receptivity to chromium by nickel deposited from baths containing a member of this pre-' ferred class of brighteners is unusual; other nickel deposits incur a noticeable decrease in chromium receptivity after a first chromium deposit has been stripped from the nickel. Moreover, receptivity is unexpected inasmuch as a significantly lower degree of chromium receptivity is obtained using the thiazine, piperizine-and piperidine analogues of these compounds. Other known compounds having excellent utility as brighteners such as N-propargylpyridinium bromide, '3-butyne-2-ol, 1,4- dicyano-butene-2, fuchsin, 3-N,N-diethylaminopropyne-1, and propargyl alcohol when tested under substantially identical conditions are not nearly so good for obtaining receptivity to chromium as are the instant thiazine dioxide and piperidone derivatives.

Good receptivity to chromium is especially significant in the automotive industry where literally millions of parts are chromium plated by mass production methods. Problems in chromium plating under these conditions are magnified because of the great number of parts being plated and because many of these parts are of different complex shapes. There is always a certain percentage of the chromium plated parts which will have defects in the surface and must be stripped and replated with chromium.

The preferred subgroup of compounds of the present invention which may be used to impart good chrome receptivity to a nickel deposit is represented by the following general formula X represents an anion selected from the group consisting of chloride, bromide, iodide, perchlorate, arylsulfonate and alkylsulfate.

Examples of specific compounds represented by the above general formula include N-propargyl thiazine-l,1- dioxide, N-propargyl-N-methyl thiazinium-1,1-dioxide bromide, N-propargyl-N-ethyl thiazinium 1,1 dioxide bromide, N-propargyl-N-propyl thiazinium-1,1-dioxide bromide, N-propargyl-N-allyl thiazinium-1,1-dioxide bromide, N-propargyl-N benzyl thiazinium-1,1-dioxide bromide, N,N dipropargyl thiazinium 1,1 dioxide bromide, 4-keto-1 propargyl piperidine, 4-keto-1-methyl-1 propargylpiperidinium bromide, 4-ket0-1-ethyl-1 propargylpiperidinium bromide, 4-keto-1-propyl-l propargylpiperidinium bromide, 4-keto-1-allyl-1 propargylpiperidinium bromide, 4-keto-l-benzyl-l-propargylpiperidinium bromide and 4-keto-1,1-dipropargylpiperidinium bromide.

It has been found that very good brighteners may be made by replacing the triple bond-containing radicals of Formula I with a double bond-containing radical. Fully bright nickel deposits may be obtained from all of the nickel baths mentioned in column 1 using N-allylthiazinef 1,1-dioxide. An excellent electroplating bath useful for obtaining a fully bright nickel deposit is obtained using the composition of Example X in the above table but substituting the N-phenyl-N'-propargylpiperizine with N- allylthiazine-l,l-dioxide. Generally the scope of double bond-containing brighteners is similar to that defined by the general Formula I with the triple bond substituted by the double bond.

While specific examples of the invention have been set forth hereinabove, it is not intended that the invention be limited solely thereto, but to include all of the variations and modifications fallingwithin the scope of the appended claims.

What is claimed:

1. A bath for electrodepositing nickel comprising an aqueous acid solution of at least one nickel salt, at least one organic sulfo-oxygen compound and an effective amount of a compound of the general formula (IV) Ofl'. om CH2 CH2 CH2 CH2 (mi it a).

N-(X) n C Hz-C EC R2 HCEC-(Hh on) wherein n is an integer from (L1 inclusive, A is a radical selected from the group consisting of #0 =C=O,

consisting of hydrogen, a lower alkyl and radical of the general formula wherein n A, R, and X. have the same meaning.

2. The bath of claim 1 wherein A represents the $0 radical.

3. The bath of claim 1 wherein A represents the =C=O radical.

4. The bath of claim 1 wherein said organic sulfooxygen is p,p'-oxy-bis(dibenzene sulfonamide) and wherein said compound represented by the general formula is N,N-dipropargylthiazinium-1,l-dioxide bromide.

5. The bath of claim 1 wherein said organic sulfooxygen compound is bid-ibenzene sulfonamide) and wherein said compound represented by the general formula is N,N-dipropargylthiazinium-l,l-dioxide benzenesulfonate.

6. The bath of claim 1 wherein said organic sulfooxygen compound is sodium allyl sulfonate and wherein said compound represented by the general formula is N-propargylthiazine 1,1-dioxide.

7. The bath of claim 1 wherein said organic sulfooxygen compound is p,p'-oxy-bis (dibenzene sulfonimide) and wherein said compound represented by the general formula is N allyl N propargylthiazinium-l,l-diox ide bromide.

8. The bath of claim 1 wherein said organic sulfooxygen compound is p,p'oxy-bis(dibenzene sulfonimide) and wherein said compound represented by the general formula is 4-keto-l-methyl-l-propargylpiperidinium bromide.

9;. The bath of claim 1 wherein said organic sulfooxygen compound is p,p-oxy-bis(dibenzene sulfonimide) and wherein said compound represented by the general formula is N,N-dipropargylthiazinium-1,l-dioxidc bromide.

References Cited by the Examiner UNITED STATES PATENTS 2,712,522 7/1955 Kardos et al. 20449 2,800,442 7/1957 Brown 20449 2,905,602 9/1959 Kirstahler et a1. 20449 X 3,006,822 10/1961 Todt 20449 3,054,733 9/1962 Heiling 20449 JOHN H. MACK, Primary Examiner.

G. KAPLAN, Assistant Examiner. 

1. A BATH FOR ELECTRODEPOSITING NICKEL COMPRISING AN AQUEOUS ACID SOLUTION OF AT LEAST ONE NICKEL SALT, AT LEAST ONE ORGANIC SULFO-OXYGEN COMPOUND AND AN EFFECTIVE AMOUNT OF A COMPOUND OF THE GENERAL FORMULA 